Hi and welcome

I would go back to your doctor and be totally honest with them. They can't really help you if they don't know whats going on. I've brought a friend to the hospital with a whole list of illegal drugs in his body and all the doctors did was help him. He even got discharged with no problem, so I'm thinking you'll be okay.
I don't have any personal experience with this but you would be right to try and quit smoking and stop snorting until the problem with your lungs gets figured out. Have things gotten worse or stayed the same? Keep us posted if you can.
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